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ORIGINAL RESEARCH ARTICLE
Dosimetric analysis of the cone beam-focused gamma knife
Shan-Chuan Li1,2 ,
Shao-Run Gong3 ,
Xiao-Feng Zhang2 ,
Gang Li3 ,
Feng Zhang2 ,
Jun-Feng Wang2* ,
Shuang Zhang2 ,
Chun-Li Zhang3 ,
Jun Li3
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1
Xi’an Zhenhe Medical Technology Company Limited, Xi’an, Shaanxi,
China
2
CNNC Cheng Imaging (Xi’an) Medical Equipment Company Limited, Xi’an, Shaanxi,
China
3
CNNC High Energy Equipment (Tianjin) Company Limited, Tianjin,
China
ARNM, 6280 https://doi.org/10.36922/arnm.6280
Submitted: 19 November 2024 | Revised: 5 February 2025 | Accepted: 5 February 2025 | Published: 3 March 2025
© 2025 by the Author(s). This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution 4.0 International License ( https://creativecommons.org/licenses/by/4.0/ )
Abstract
This study presents the first report on the fundamental dosimetric characterization of a novel image-guided radiosurgery system – the ZND-A Smart Knife (CNCI Co., Ltd, Xi’an, China). The dosimetric performance of this radiosurgery system was evaluated based on key parameters, including positioning reference point deviation, nominal focal point dose rate, focusing field size, dose gradient, and comprehensive error in dose calculation. The system employs “triple rotating and focusing” technique, and its dosimetric characteristics were measured. The maximum positioning reference point deviation for collimator #1 – 4 was 0.38 mm; the corresponding dose gradients were 3.1 mm, 3.4 mm, 5.4 mm, and 7.7 mm, respectively. In dose calculation, the maximum isocenter point dose deviation was 3.3%, and the area overlap ratio for the largest collimator (#4) reached 98.3%. These results demonstrate excellent dosimetric performance and clinical potential, confirming the safety and precision of the next-generation cone beam-focused gamma knife system.
Keywords
Cone beam-focused gamma knife
EBT3 film
Electrostatic meter
Radiation dosimetry
Stereotactic radiation therapy
Funding
This research is funded by the CNNC research project “Smart Cobalt 60 cone beam-focused SRT system research and development”.
Conflict of interest
All the authors are employees of CNNC.
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